如何获取elasticsearch中的最大_id值？

我们使用自定义的_id字段是一个long价值。我想获得最大 _id 值。我正在进行的搜索是 -

{
  "stored_fields": [
    "_id"
  ],
  "query": {
    "match_all": {}
  },
  "sort": {
    "_id": "desc"
  },
  "size": 1
}

但我从 ES 5.1 收到错误消息：

"reason": {
              "type": "illegal_argument_exception",
              "reason": "Fielddata access on the _uid field is disallowed"
}

那么，我该如何获得最大值_id。我真的不想存储副本_id在文档中只是为了获取最大值。

您应该按_uid字段不由_id场地。这_id无法访问字段进行排序（https://www.elastic.co/guide/en/elasticsearch/reference/current/mapping-id-field.html https://www.elastic.co/guide/en/elasticsearch/reference/current/mapping-id-field.html).

{
  "stored_fields": [
    "_id"
  ],
  "query": {
    "match_all": {}
  },
  "sort": {
    "_uid": "desc"
  },
  "size": 1
}